Display panel with touch detection function, method of driving the same, drive circuit, and electronic unit

Abstract

There are provided a display panel with a touch detection function and a method of driving the same, a drive circuit, as well as an electronic unit, which make it possible to reduce an influence of a disturbance noise. The display panel includes: a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period; a display section performing display based on the synchronization signal; and a touch detection section performing touch detection operation based on the synchronization signal.

What is claimed is: 
     
       1. A display panel with a touch detection function, the display panel comprising:
 a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period; 
 a display section performing display based on the synchronization signal; 
 a touch detection section performing touch detection operation based on the synchronization signal; and 
 a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise. 
 
     
     
       2. The display panel according to  claim 1 , wherein the display section performs display for one screen in a pulse duration in which the series of pulses continues. 
     
     
       3. The display panel according to  claim 2 , wherein the touch detection section performs the touch detection operation in the pulse duration. 
     
     
       4. The display panel according to  claim 3 , wherein the touch detection section performs the touch detection operation, also in a blanking period other than the pulse duration. 
     
     
       5. The display panel according to  claim 4 , wherein the pulse duration is equal to or shorter than a predetermined length. 
     
     
       6. The display panel according to  claim 1 , wherein the pulse period is set by a clock count of a base clock, and
 the pulse period is changed by changing a clock frequency of the base clock. 
 
     
     
       7. The display panel according to  claim 1 , wherein the signal generation section selects the pulse period based on a detection result in the touch detection section. 
     
     
       8. The display panel according to  claim 2 , wherein the pulse duration is included in a frame period based on an image signal supplied. 
     
     
       9. The display panel according to  claim 1 , further comprising:
 a plurality of drive electrodes arranged side by side to extend in one direction; 
 a detection electrode arranged side by side to extend in a direction intersecting the drive electrode; 
 a plurality of pixel electrodes; and 
 a display element performing display based on a voltage of the drive electrode and a voltage of the pixel electrode, 
 wherein, based on the synchronization signal, the display section performs display by driving and thereby sequentially scanning a plurality of the display elements per a plurality of the display elements corresponding to each of the drive electrodes, and at timing synchronized with the synchronization signal, the touch detection section sequentially applies a drive signal to the plurality of drive electrodes, and detects a touch event based on a detection signal outputted from the detection electrode. 
 
     
     
       10. The display panel according to  claim 9 , wherein the plurality of drive electrodes form a plurality of drive electrode blocks each including a predetermined number of the drive electrodes, and
 the touch detection section applies the drive signal to each of the drive electrode blocks, for each drive period including a predetermined number of the pulse periods. 
 
     
     
       11. The display panel according to  claim 10 , wherein the touch detection section allows the drive period to be long, when the pulse duration is equal to or shorter than a predetermined length. 
     
     
       12. A method of driving a display panel with a touch detection function, the method comprising:
 selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal that includes a series of pulses appearing at the selected pulse period; 
 performing display for one screen, and performing touch detection operation, based on the series of pulses of the synchronization signal; 
 switching display of a screen, for each predetermined frame period; and 
 changing the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise. 
 
     
     
       13. A drive circuit comprising:
 a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal that includes a series of pulses appearing at the selected pulse period; 
 a display drive section driving a display panel based on the synchronization signal; 
 a touch-detection drive section driving a touch panel based on the synchronization signal; and 
 a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise. 
 
     
     
       14. An electronic unit including a display panel with a touch detection function, and a control section performing operation control using the display panel, the display panel comprising:
 a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period; 
 a display section performing display based on the synchronization signal; 
 a touch detection section performing touch detection operation based on the synchronization signal; and 
 a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise.